Vibrator unit and portable telephone employing it

ABSTRACT

A vibrating device that can be applied to various purposes other than as a vibrator and that can achieve cost reduction, size reduction, and space saving by a reduction in the number of components, and a mobile phone using this vibrating device are provided. The vibrating device has a housing supported by a base and capable of oscillating in a vibration frequency range of a vibrator, and an expandable rod that can expand and contract, one end of which is fixed to the housing, and the other end of which is a free end contacting the base. The base is resonated by oscillation of the housing in the vibration frequency range of a vibrator, while the base is vibrated by expansion and contraction of the expandable rod in a sound frequency range other than the vibration frequency range of a vibrator.

TECHNICAL FIELD

The present invention relates to a vibrating device and a mobile phoneusing the same, and more particularly to a vibrating device that can beapplied to various purposes other than as a vibrator and that canachieve cost reduction, size reduction, and space saving by a reductionin the number of components, and a mobile phone using this vibratingdevice.

BACKGROUND ART

Conventionally, there have been widely known mobile phones that vibrateto indicate a phone call (see, for example, Japanese Patent Laid-OpenPublication No. Hei 9-18555).

Generally, the mobile phone of this type employs a vibrating device thatgenerates vibration by rotating an eccentric weight with a motor,whereby its casing is vibrated.

However, these conventionally known vibrating devices tend to be largebecause of the use of a motor, and were not necessarily most suitablefor mobile phones, which are required to be small. Moreover, it hasbecome common in recent years that a mobile phone includes a camera, arecording device, and the like therein in addition to the vibratingdevice, and so a reduction of the number of components and space savingin the phone are demanded.

DISCLOSURE OF THE INVENTION

The present invention was devised to solve these problems, and an objectof the invention is to provide a vibrating device that can be applied tovarious purposes other than as a vibrator and that can achieve costreduction, size reduction, and space saving by a reduction in the numberof components, and a mobile phone using this vibrating device.

As a result of study, the inventor of the present invention hasdeveloped a vibrating device that can be applied to other purposes thanas a vibrator and a mobile phone using the same.

In other words, the following present invention can achieve theforegoing object.

(1) A vibrating device having: a housing supported by a base and capableof oscillating relative to the base in a vibration frequency range of avibrator; and an expandable rod that can expand and contract, one end ofwhich is fixed to the housing, and the other end of which is a free endcontacting the base, wherein the base is resonated by oscillation of thehousing in the vibration frequency range of a vibrator, and the base isvibrated by expansion and contraction of the expandable rod in a soundfrequency range other than the vibration frequency range of a vibrator.

(2) The vibrating device according to (1), wherein the housing includesan inertial mass member, and the one end of the expandable rod is fixedto the inertial mass member.

(3) The vibrating device according to (1) or (2), wherein the housing issupported on the base by a support member having vibration transmissioncharacteristics that allow oscillation of the housing in the vibrationfrequency range of a vibrator and restrict oscillation of the housing inthe sound frequency range.

(4) The vibrating device according to (3), wherein the support membersupports part of the housing such that the housing can oscillate aroundthe vicinity of the part acting as a fulcrum point, and supports anotherpart of the housing a distance away from the part via a resilient memberhaving the vibration transmission characteristics.

(5) The vibrating device according to (3), wherein the support membersupports the housing in a suspended state such that the housing canoscillate around the free end of the expandable rod acting as a fulcrumpoint, and has a resilient member having the vibration transmissioncharacteristics in a direction of oscillation of the housing.

(6) The vibrating device according to any one of (1) to (5), wherein atleast part of the expandable rod is formed of a displacement rod made ofa displacement element.

(7) The vibrating device according to (6), wherein the expandable rod isformed of the displacement rod and a transmission rod having the freeend for transmitting a displacement in the displacement rod to the base,the free end of the transmission rod being contacted to the base at aposition offset from an axial center of the displacement rod.

(8) The vibrating device according to (6) or (7), wherein thedisplacement rod is made of a magnetostrictive element including a giantmagnetostrictive element.

(9) The vibrating device according to (8), further comprising:

a biasing magnet arranged at both axial ends of the displacement rodmade of the magnetostrictive member, for applying a bias magnetic fieldto the displacement rod in an axial direction; and

a magnet coil arranged to surround the displacement rod, for causing thedisplacement rod to expand and contract by controlling intensity of theapplied magnetic field.

(10) A mobile phone characterized in that the vibrating device accordingto any one of (1) to (9) is provided in a casing.

(11) The mobile phone according to (10), wherein the casing serves as aspeaker of a receiver for generating a conversation sound, a speaker ofa call alert buzzer, and a vibrating member of a call alert vibrator.

(12) The mobile phone according to (11), wherein the vibrating deviceserves as a speaker vibrating device of the receiver, a speakervibrating device of the call alert buzzer, and a vibrating device of thecall alert vibrator.

(13) The mobile phone according to (11) or (12), wherein the speaker ofthe receiver is a bone conduction speaker that uses the principle ofbone conduction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross-sectional view showing a side cross sectionof a vibrating device according to an exemplary embodiment of thepresent invention;

FIG. 2 is a front view of the same vibrating device;

FIG. 3 is a simplified block diagram schematically showing a drivecircuit of the vibrating device of FIG. 1; and

FIG. 4 is a schematic cross-sectional view showing a side cross sectionof a vibrating device according to another exemplary embodiment of thepresent invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Exemplary embodiments of the present invention will be hereinafterdescribed with reference to the drawings.

One example, in which the vibrating device 10 according to one exemplaryembodiment of the present invention is provided in a casing 12 (onlypartly shown) of a mobile phone, is described with reference to FIG. 1.

As shown in FIG. 1, the vibrating device 10 generally comprises: agenerally cylindrical housing 14; first and second support members 16and 18, an inertial mass member 20; an expandable rod 22; and agenerally cylindrical magnet coil 24. The housing 14 is disposedvertically in FIG. 1 on the casing (base) 12 of the mobile phone. Thefirst and second support members 16 and 18 are arranged on the right andleft in FIG. 1 for supporting the housing 14. The inertial mass member20 is disposed in an upper part of the interior of the housing 14. Theexpandable rod 22 is arranged vertically below the inertial mass member20 such that its one end extends through the bottom of the housing 14.The magnet coil 24 is arranged to surround the expandable rod.

Two, first and second, support frame portions 14A and 14B are integrallyformed with the generally cylindrical housing 14 around itscircumference at the bottom (see FIG. 2). The first support frameportion 14A on the right side in the drawing is supported by the firstsupport member 16 consisting of a rod-like member 26 integrally formedwith the casing 12 and a screw 28 coupled therewith.

On the other hand, the second support frame portion 14B on the left sidein the drawing is supported by the second support member 18 formed oftwo resilient members 30A and 30B and a long screw 32. Morespecifically, the second support frame portion 14B is provided with ahole that is slightly larger than the outside diameter of the screw 32fixedly fastened to the casing 12, and is structured to be movable inthe up and down directions in the drawing, with the screw 32 beingfitted therein. On the upper and lower sides of the second support frameportion 14B are arranged the two resilient members 30A and 30Brespectively, such that the second support frame portion 14B issupported by these two resilient members 30A and 30B holding its upperand lower sides.

In other words, the housing 14 is displaceable in the up and downdirections in the drawing on the side of the second support frameportion 14B, having a structure capable of oscillating around thevicinity of the first support frame portion 14A acting as a fulcrumpoint. The resilient members 30A and 30B forming the second supportmember 18 have vibration transmission characteristics that allowoscillation of the housing 14 in a vibration frequency range of avibrator and restrict the oscillation of the housing 14 in a soundfrequency range.

Here, the “vibration frequency range of a vibrator” in the presentinvention refers to a frequency range of from several tens to severalhundreds Hz, meaning the frequency range that is generally used fordriving a vibrator. The “sound frequency range” in the present inventionrefers to a frequency range of from several hundreds Hz to several tenskHz other than the vibration frequency range of a vibrator, meaning thegeneral audible frequency range for the human ear.

Referring back to FIG. 1, the expandable rod 22 arranged verticallybelow the inertial mass member 20 is formed of a generally columnardisplacement rod 34, two biasing magnets 36 and 38 arranged at bothaxial ends of the displacement rod 34 for applying a bias magnetic fieldto the displacement rod 34 in the axial direction, and a transmissionrod 40 arranged axially below the displacement rod 34.

The generally columnar displacement rod 34 consists of a giantmagnetostrictive member made of a giant magnetostrictive element. The“giant magnetostrictive element” refers to a magnetostrictive elementmade of a powder sintered alloy or a single-crystal alloy that is mainlycomposed of a rare earth element and/or specified transition metal (forexample, terbium, dysprosium, iron and the like); the element has acharacteristic that it generates a large displacement when a magneticfield is applied externally (magnetostrictive effect) The two biasingmagnets 36 and 38 are tightly fixed to both axial ends of thedisplacement rod 34 on one side, while the other side of the biasingmagnet 36 that is on the upper side in FIG. 1 is tightly fixed to theinertial mass member 20, and the other side of the biasing magnet 38 onthe lower side in the drawing is tightly fixed to the transmission rod40.

This transmission rod 40 is formed by attaching a component 40C havingan inverted triangular side face to one end of a generally columnarmember 40B having a disc-like flange portion 40A to be in one-piecetherewith such that one top 40D of the triangle is offset from the axialcenter L1 of the generally columnar member 40B, the top 40D being thefree end of the transmission rod 40. In other words, the free end 40D ofthe transmission rod 40 is contacted to the casing 12 at a positionoffset by a distance El from the axial center L1 of the displacement rod34. Between the flange portion 40A of the transmission rod 40 and thehousing 14 are arranged springs 42A and 42B to bias the flange portion40A away from the housing 14.

The generally cylindrical magnet coil 24 is arranged to surround theouter circumference of the displacement rod 34 of the expandable rod 22,and has a structure that allows control of the intensity of the magneticfield applied to the displacement rod 34. To the magnet coil 24 isconnected a pulse oscillator 48, which is the drive power supply sourceof the displacement rod 34, via a coupling condenser 46. The pulseoscillator 48 is configured such as to be capable of outputting bothvibration pulses in the vibrator frequency range and sound pulses in thesound frequency range.

Next, how the vibrating device 10 operates is described with referencealso to the simplified block diagram of FIG. 3.

When a call signal is input to a signal receiving section 60 of themobile phone, the call signal is transmitted to a control circuit 62.The control circuit 62 then decides whether the call recipient shall bealerted by a call alert s buzzer (sound) or a call alert vibrator(vibration), depending on the mode generally provided in the mobilephone.

When alerting the call recipient by the buzzer, a sound pulse signal inthe sound frequency range is generated in a sound frequency generationcircuit 64 and supplied to the magnet coil 24. The sound pulse signalsupplied to the magnet coil 24 changes the intensity of the magneticfield applied to the displacement rod 34. As a result, an axialdisplacement is generated in the displacement rod 34 due to themagnetostrictive effect, causing the expandable rod 22 to repeatexpansion and contraction at a sound frequency.

In this case, since the free end 40D of the expandable rod 22 iscontacted to the casing 12, the stress applied from the expandable rod22 causes the housing 14 to oscillate, with the first support frameportion 14A acting as a fulcrum point. However, as noted above, theresilient members 30A and 30B of the second support member 18 havevibration transmission characteristics that restrict oscillation of thehousing 14 in the sound frequency range. Therefore, when a sound pulsesignal in the sound frequency range is supplied to the magnet coil 24,the oscillation of the housing 14 is restricted, and the casing 12 isvibrated at a sound frequency by the expansion and contraction of theexpandable rod 22. Thus the sound pulse signal of the buzzer isconverted into the vibration of the casing 12, which serves as a speakerto output the sound.

On the other hand, when alerting the call recipient by the vibrator, avibration pulse signal in the vibrator frequency range is generated in avibrator frequency generation circuit 66 and supplied to the magnet coil24. As a result, as with the buzzer, a displacement is generated in thedisplacement rod 34 due to the magnetostrictive effect, causing theexpandable rod 22 to repeat expansion and contraction at a vibratorfrequency.

In this case, as noted above, since the resilient members 30A and 30B ofthe second support member 18 have vibration transmission characteristicsthat allow oscillation of the housing 14 in the vibrator frequencyrange, the housing 14 oscillates around the first support frame portion14A acting as a fulcrum point, and this oscillation resonates the casing12. Thus the vibration pulse signal of the vibrator is transmitted tothe outside by the resonance of the casing 12.

When the signal receiving section 60 receives a sound signal of aconversation sound, it is converted into vibration of the casing 12 viathe same path as with the buzzer, and the casing 12 serves as a speakerto output the sound. In this case, however, the casing 12 can output thesound at a lower sound level than the case with the sound signal of thebuzzer from the sound frequency generation circuit 64, because thecasing 12 can function as a bone conduction speaker that uses theprinciple of bone conduction.

With the vibrating device 10 according to the exemplary embodiment ofthe present invention, in the vibration frequency range of a vibrator,the casing 12 is resonated by the oscillation of the housing 14, whilein the sound frequency range other than the vibration frequency range ofa vibrator, the casing 12 is vibrated by the expansion and contractionof the expandable rod 22, whereby the vibrating device 10 can be appliedto various purposes other than as a vibrator. Accordingly, as notedabove, by providing this vibrating device 10 in the casing 12 of themobile phone, the vibrating device 10 can be made to function as aspeaker vibrating device of the receiver, a speaker vibrating device ofthe call alert buzzer, and a vibrating device of the call alertvibrator, whereby cost reduction, size reduction, and space saving areachieved by a reduction in the number of components. Moreover, as thecasing 12 functions as the speaker of the receiver for generating aconversation sound, the speaker of the call alert buzzer, and avibrating member of the call alert vibrator, further reductions in thecost, size and the like are possible.

Also, as the displacement rod 34 consists of a giant magnetostrictivemember made of a giant magnetostrictive element, an increase in thevibration intensity can be achieved while achieving size reduction ofthe device at the same time.

Furthermore, because the expandable rod 22 is formed of the displacementrod 34 and the transmission rod 40 and the free end 40D of thetransmission rod 40 is contacted to the casing 12 at a position offsetfrom the axial center L1 of the displacement rod 34, the vibrationintensity of the oscillation of the housing 14, i.e., of the resonanceof the casing 12, in the vibrator frequency range can be increased witha simple structure.

It should be noted that the present invention should not be limited tothe structure, shape and the like of the vibrating device 10 accordingto the above-described exemplary embodiment and the invention includesother designs as long as the vibrating device has a housing supported ona base and capable of oscillating in a vibration frequency range of avibrator, and an expandable rod that can expand and contract, one end ofwhich is fixed to the housing, and the other end of which is a free endcontacting the base. Accordingly, a vibrating device 70 shown in FIG. 4,for example, is also included in the invention.

This vibrating device 70 employs a generally cylindrical case-like outerhousing 72 instead of the first and second support members 16 and 18 ofthe above-described vibrating device 10 shown in FIG. 1. The featuressimilar to the vibrating device 10 will not be described again.

The generally cylindrical case-like outer housing 72 is rigidly attachedto the casing 12 with two pairs of bolts 74A and 74B and nuts 76A and76B. A housing 80 having a transmission rod 78 and others isaccommodated inside the outer housing 72 vertically in the drawing.

The housing 80 is supported in a suspended state with a spring 82 hungfrom the top inside the outer housing 72, and is also supported by thetransmission rod 78 extending to the outside of the outer housing 72, tohave a structure capable of oscillating around the free end 78A of thetransmission rod 78 acting as a fulcrum point. In the inner surface ofthe outer housing 72 in a direction in which the housing 80 oscillatesis arranged a resilient member 84 such as to surround the side face ofthe housing 80. The resilient member 84 has vibration transmissioncharacteristics that allow oscillation of the housing 80 in a vibrationfrequency range of a vibrator and restrict the oscillation (movements ofthe housing 80 in the axial direction L2 and in the radial direction) ofthe housing 80 in a sound frequency range.

The transmission rod 78 is formed by attaching a circular end face 78D1of a generally semi-spherical member 78D to one end of a generallycolumnar member 78C having a disc-like flange portion 78B such that thecenter of the circular end face is offset from the axial center L2 ofthe generally columnar member 78C. In other words, the free end 78A ofthis transmission rod 78 is contacted to the casing 12 at a positionoffset by a distance E2 from the axial center L2 of the transmission rod34.

The vibrating device 70 operates as follows.

When a sound pulse signal in the sound frequency range is supplied tothe magnet coil 24, causing the expandable rod 86 to expand and contractat a sound frequency, the stress applied from the expandable rod 86causes the housing 80 to oscillate, with the free end 78A of theexpandable rod 86 acting as a fulcrum point. However, as noted above,the resilient member 84 has vibration transmission characteristics thatrestrict oscillation of the housing 80 in the sound frequency range.Therefore, when a sound pulse signal in the sound frequency range issupplied to the magnet coil 24, the oscillation (movements of thehousing 80 in the axial direction L2 and in the radial direction) of thehousing 80 is restricted, and the casing 12 is vibrated at a soundfrequency by the expansion and contraction of the expandable rod 86.Thus the sound pulse signal of the buzzer or a conversation sound isconverted into the vibration of the casing 12, which serves as a speakerto output the sound.

On the other hand, when a vibration pulse signal in the vibratorfrequency range is supplied to the magnet coil 24, the housing 80oscillates around the free end 78A of the expandable rod 86 acting asthe fulcrum point because the resilient member 84 has vibrationtransmission characteristics that allow oscillation of the housing 80 inthe vibration frequency range of a vibrator, and this oscillationresonates the casing 12. Thus the vibration pulse signal of the vibratoris transmitted to the outside by the resonance of the casing 12.

The same effects as with the above-described vibrating device 10 can beachieved with this vibrating device 70.

While the displacement rod 34 of the expandable rod 22 consists of agiant magnetostrictive member made of a giant magnetostrictive elementin the above-described exemplary embodiment, the present invention isnot limited to this. Therefore, for example, the rod may be made of amagnetostrictive element, or of any other displacement elements such asa piezoelectric element or the like.

The purpose of use of the vibrating device according to the presentinvention should not be limited to mobile phones.

INDUSTRIAL APPLICABILITY

The vibrating device of the present invention can be applied to variouspurposes other than as a vibrator, and provides excellent effects suchas cost reduction, size reduction, and space saving by a reduction inthe number of components.

1-13. (canceled)
 14. A vibrating device having: a housing supported by abase and capable of oscillating relative to the base in a vibrationfrequency range of a vibrator; and an expandable rod that can expand andcontract, one end of which is fixed to the housing, and the other end ofwhich is a free end contacting the base, wherein the base is resonatedby oscillation of the housing in the vibration frequency range of avibrator, and the base is vibrated by expansion and contraction of theexpandable rod in a sound frequency range other than the vibrationfrequency range of a vibrator.
 15. The vibrating device according toclaim 14, wherein the housing includes an inertial mass member, and theone end of the expandable rod is fixed to the inertial mass member. 16.The vibrating device according to claim 14, wherein the housing issupported on the base by a support member having vibration transmissioncharacteristics that allow oscillation of the housing in the vibrationfrequency range of a vibrator and restrict oscillation of the housing inthe sound frequency range.
 17. The vibrating device according to claim15, wherein the housing is supported on the base by a support memberhaving vibration transmission characteristics that allow oscillation ofthe housing in the vibration frequency range of a vibrator and restrictoscillation of the housing in the sound frequency range.
 18. Thevibrating device according to claim 16, wherein the support membersupports part of the housing such that the housing can oscillate aroundthe vicinity of the part acting as a fulcrum point, and supports anotherpart of the housing a distance away from the part via a resilient memberhaving the vibration transmission characteristics.
 19. The vibratingdevice according to claim 16, wherein the support member supports thehousing in a suspended state such that the housing can oscillate aroundthe free end of the expandable rod acting as a fulcrum point, and has aresilient member having the vibration transmission characteristics in adirection of oscillation of the housing.
 20. The vibrating deviceaccording to claim 14, wherein at least part of the expandable rod isformed of a displacement rod made of a displacement element.
 21. Thevibrating device according to claim 15, wherein at least part of theexpandable rod is formed of a displacement rod made of a displacementelement.
 22. The vibrating device according to claim 16, wherein atleast part of the expandable rod is formed of a displacement rod made ofa displacement element.
 23. The vibrating device according to claim 18,wherein at least part of the expandable rod is formed of a displacementrod made of a displacement element.
 24. The vibrating device accordingto claim 19, wherein at least part of the expandable rod is formed of adisplacement rod made of a displacement element.
 25. The vibratingdevice according to claim 20, wherein the expandable rod is formed ofthe displacement rod and a transmission rod having the free end fortransmitting a displacement in the displacement rod to the base, thefree end of the transmission rod being contacted to the base at aposition offset from an axial center of the displacement rod.
 26. Thevibrating device according to claim 20, wherein the displacement rod ismade of a magnetostrictive element including a giant magnetostrictiveelement.
 27. The vibrating device according to claim 25, wherein thedisplacement rod is made of a magnetostrictive element including a giantmagnetostrictive element.
 28. The vibrating device according to claim26, further comprising: a biasing magnet arranged at both axial ends ofthe displacement rod made of the magnetostrictive member, for applying abias magnetic field to the displacement rod in an axial direction; and amagnet coil arranged to surround the displacement rod, for causing thedisplacement rod to expand and contract by controlling intensity of theapplied magnetic field.
 29. A mobile phone characterized in that thevibrating device according to claim 14 is provided in a casing.
 30. Themobile phone according to claim 29, wherein the casing serves as aspeaker of a receiver for generating a conversation sound, a speaker ofa call alert buzzer, and a vibrating member of a call alert vibrator.31. The mobile phone according to claim 30, wherein the vibrating deviceserves as a speaker vibrating device of the receiver, a speakervibrating device of the call alert buzzer, and a vibrating device of thecall alert vibrator.
 32. The mobile phone according to claim 30, whereinthe speaker of the receiver is a bone conduction speaker that uses theprinciple of bone conduction.
 33. The mobile phone according to claim31, wherein the speaker of the receiver is a bone conduction speakerthat uses the principle of bone conduction.